烧瓶棉花糖自定义字段

Question

我使用烧瓶棉花糖和mongoengine。

还有我的API服务器的烧瓶休息加。

这是我的 api.py

class BoardSchema(ma.Schema):
class Meta:
fields = ('no', 'title', 'body', 'tags', 'created_at', 'views')
board_schema = BoardSchema()
boards_schema = BoardSchema(many=True)

class ArticleList(Resource):
def get(self):
articles = Board.objects.all()
return boards_schema.jsonify(articles)

model.py

from datetime import datetime
from mongoengine import *
from config import DB_NAME

connect(DB_NAME)

class Board(Document):
d = datetime.now()
date = "{}-{}-{}".format(d.year, d.month, d.day)
no = SequenceField()
title = StringField(required=True)
body = StringField(required=True)
tags = ListField(StringField())
likes = ListField(StringField())
views = ListField(StringField())
password = StringField(required=True)
created_at = DateTimeField(default=date)
updated_at = DateTimeField(default=date)

当我访问/article 时，结果是这样的 ->

{
"body": "123", 
"created_at": "2018-08-20T00:00:00+00:00", 
"no": 1, 
"tags": [
"MySQL", 
"C"
], 
"title": "ud14cuc2a4ud2b8", 
"views": [
"127.0.0.1"
]
}

在"views"，将添加阅读文章的IP。

但是我想计算所有视图列表并将其包含在我的结果中。

我想要的结果就在这里。

{
"body": "123", 
"created_at": "2018-08-20T00:00:00+00:00", 
"no": 1, 
"tags": [
"MySQL", 
"C"
], 
"title": "ud14cuc2a4ud2b8", 
"views": 20
}

我是烧瓶棉花糖的新手，所以我很困惑如何解决这个问题。

谢谢。

Answer 1

也许你可以这样尝试：

class BoardSchemaCustom(ma.ModelSchema):
class Meta:
model = Board
views = ma.fields.method(deserialize="_custom_serializer")
def _custom_serializer(self, obj):
return len(obj.views)

创建自定义架构的实例：

custom_board_schema = BoardSchemaCustom()

并转储它：

dump, errors = custom_board_schema.schema.dump(Board.query.first())
>>> dump

Answer 2

我有同样的问题。 我的代码在安装棉花糖-SQLllChemy后工作

pip install marshmallow-sqlalchemy

参见官方文档 https://flask-marshmallow.readthedocs.io/en/latest/

Answer 3

下面的代码片段也可以工作：

class BoardSchemaCustom(ma.ModelSchema):
class Meta:
model = Board
views = ma.fields.Function(lambda obj: len(obj.views))